145 - Exmoor : Natural Capital and Key Ecosystem Services

Introduction

The Exmoor NCA provides a wide range of benefits to society. Each derives from the attributes and processes (both natural and cultural features) within the area. These benefits are known collectively as ‘ecosystem services’. The predominant services are summarised below (under the constituent headings). Further information on ecosystem services provided in the Exmoor NCA is contained in the ‘Analysis’ section of this website.

What is Natural Capital?

Natural capital means “the elements of nature that directly or indirectly produce value to people, including ecosystems, species, freshwater, land, minerals, the air and oceans, as well as natural processes and functions” (Natural Capital Committee, 2017).

It is helpful to consider natural capital in the form of a logic chain that represents the links between ecosystem assets, services, benefits and value to people. The figure below displays that logic chain. The quantity and quality of ecosystem assets (woodland, bogs, etc) support different types of ecosystem services, such as carbon sequestration or water filtration. These ecosystem services then provide different benefits to society, providing value for people. The figure also shows how management interventions, as well as pressures and drivers of change, influence this chain. Other capital inputs are also often needed for people to obtain the benefits from ecosystem services (a simple example is the processing of trees to produce wood products).

As an example, an area of woodland (ecosystem asset) may reduce air pollution created by traffic on a nearby road. This woodland is therefore improving air quality (ecosystem service) in the local area which results in cleaner air and improved health in the adjacent residential street (benefit). This cleaner air has a value because we know it impacts the health and wellbeing of communities.

Sometimes for ease of understanding, economic framing is used to give these benefits a monetary value. The figure below shows how natural capital assets support the provision of ecosystem services, benefits and value. The roots of the tree show how aspects of asset quality are critical to the provision of ecosystem services. The roots also show that geodiversity underpins the ecosystem assets and therefore the ecosystem services and benefits they can provide. It is important to remember that this diagram, and natural capital frameworks more generally, are a simplification of how nature works in practice.

Natural Capital within this NCA

In 2018, Natural England published ‘Natural Capital Indicators: for defining and measuring change in natural capital’ (Lusardi et al., 2018). This report identified key properties of the natural environment vital for the long-term sustainability of benefits, which can act as indicators of change.

These indicators are designed to inform our understanding of the state of our natural assets. The indicators highlight the importance of our natural assets for delivering which ecosystem service and the benefits they provide for society. The indicators and datasets identified in Natural England’s Natural Capital Indicators Project provide the foundation for the Natural Capital Atlas Profiles.

Natural England’s Natural Capital Atlas Profiles provide an “off the shelf” natural capital evidence base for each county or city region. They have a wide variety of uses with more information in the How to Start Using Your Natural Capital Atlas.

The Natural Capital indicators are presented on the map below by broad asset theme, displaying the natural capital within the NCA.

It is noted that not all indicators listed within the Natural Capital Atlas Profiles are included within the map as data is not yet available to measure them. Refer to the “Indicator Gaps and Limitations” of the Natural Capital Atlas Profiles for further information.

Natural Capital Atlas Profiles

The following Natural Capital Atlas Profiles cover counties within this NCA:
 

• 9: Devon
• 34: Somerset

Provisioning services (food, fibre and water supply)

Food provision: A producer of store lambs and suckler calves with some beef and dairying. The area supported in excess of half a million sheep in 2009.

Timber provision: The main source of commercial timber from Exmoor is currently the conifer plantations on the upper moorland fringes, and some steeper slopes and valley sides. In total these plantations cover some 4 per cent of the area of this NCA. Some high-quality, specialist oak products are derived from the area.

Water availability: Much of the area forms part of the upper Exe catchment with the peatland plant communities of the open moorland storing water and feeding the headwaters of a radial pattern of rivers. The Exe and its principal tributary the Barle flow south. On the western side of the NCA the rivers Yeo, Mile and Bray drain into the River Taw. The River Tone rises at Beverton Pond near the south-eastern edge of the area. This area provides a key source of water for the region, with the Wimbleball reservoir supplying Exeter and parts of East Devon by releasing water into the River Exe. The Clatworthy reservoir, releasing water into the River Tone being a major source of water for Taunton. Most of the area is classed as having water available for abstraction, although the eastern part of the NCA is classed as either over licensed or having no further water available for abstraction. The growth of Barnstaple in the west and Exeter to the south may place further pressure on the water resources of Exmoor. For information regarding the current state of water availability within this NCA, refer to the Environment Agency (Abstraction Licensing Strategy).

Regulating services (water purification, air quality maintenance and climate regulation)

Climate regulation: Across most of the NCA, greenhouse gas regulation through carbon stored in the soils is relatively low (less than 10 per cent). The deeper peat soils, found across the extensive areas of blanket bog habitat, house significantly high volumes of atmospheric carbon, particularly along The Chains.

Regulating water flow: Steeply sloping topography occurs across most of the area resulting in fast flowing rivers and streams often descending into constricted river valleys. This can present significant flood risk and particularly where settlements have been established in the lower reaches of river valleys. High rainfall or rapid snow melt on the moorlands, particularly when running over saturated or frozen ground, can result in hazardous flash floods that threaten settlements and infrastructure downstream. The flooding of Lynmouth in 1952, which resulted in a significant loss of life and damage to property, is a severe example. A pilot study in the Aller catchment is one of three national initiatives considering whole-catchment flood management. Mires may limit the rate of water flow from the upland areas.

Regulating coastal flooding and erosion: The coast at Minehead is susceptible to coastal flooding. Analysis of the coastal processes and landforms at Porlock Bay and Braunton contribute to the understanding of the benefits that a naturally functioning coast can provide to maintain and enhance local landscapes, biodiversity, sustainability of current management practices and reduction of flooding to built areas and valuable, production land. For information regarding current shoreline management within this NCA, refer to the Environment Agency (Shoreline management plans).

Cultural services (inspiration, education and wellbeing)

Sense of place/inspiration: A landscape and coastline that has offered great inspiration through the centuries and to the present day. The open moorland and exquisite diversity of landscapes, wildness and remoteness have stimulated romantic poets, Coleridge and Wordsworth, authors, R D Blackmore, painters and photographers.

Sense of history: A landscape rich in archaeology, and particularly bronze-age remains (with standing stones, stone settings and rows, and barrows), with historic settlements, such as Dunster, and deep-rooted agricultural and coastal traditions and cultures.

Tranquillity: An intensely tranquil place of dark skies (Europe’s first International Dark Sky Reserve), uncluttered views and free, in most part, from major infrastructure.

Recreation: With a National Park, AONB and 109 km of the South West Coast Path, the area is of great importance for tourism and recreation. There are also three National Nature Reserves providing and promoting access to important habitats and species found in the area. The variety of opportunity accommodates contemplative recreation and outward bound activities, such as upland walking, mountain biking and pony trekking. The coastal towns, such as Minehead and Ilfracombe, offer a more traditional seaside holiday with many visiting the area for its fine sandy beaches. Canoeing, surfing, shooting and bird-watching are all common and popular activities supported by the area.

Biodiversity: A wealth of habitats, from moorland and blanket bog to sessile oak woodlands and parkland, as at Arlington Court, and coastal cliffs, shingle ridges and extensive sand dunes, support an array of nationally and internationally important species. These include high brown, heath and, to a lesser extent, marsh fritillary butterflies, all species of British bat, rare lichen communities and an array of common and rare birds adapted to moorland, woodland, farmland and coastal conditions. The Atlantic, oceanic climate and lack of pollution further contribute to this diversity allowing for the development of sensitive lichens, mosses and bryophytes.

Geodiversity: The ability to observe, record and interpret geological formations and geomorphological processes particularly along the coast, is an important contribution to education. The underlying geology of the area determines and influences many of the habitats and human activities found across the area.